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41.
车辆进入自适应巡航工况下行驶时,不同风格的驾驶人会对自适应巡航控制系统(Adaptive Cruise Control,ACC)有不同的需求。文章首先通过对不同驾驶人在9种跟随试验下获取的实验数据分析,选取表征驾驶人风格的驾驶特征参数;其次对所有驾驶人驾驶特征参数利用K-mean算法聚类分析,将驾驶人三类,并利用BP神经网络建立辨识模型对驾驶人风格进行辨识。结果表明;文章提出的方法可以较高的准确率对驾驶人风格进行分类,提高自适应巡航系统适应驾驶人的能力。 相似文献
42.
李余华 《华东交通大学学报》2006,23(3):69-72
中西不同的人性论预设,导致了不同的治国方略和制度路径.人性善或经验主义人性恶假设是人治和专制治理的理论基础;理性主义人性恶假设是法治的理论基础.人性善强调了道德自律的可能性,但缺乏预警机制,理性主义人性恶的不足在于过分强调人性中的阴暗,忽略了人的主动性.人性善或经验主义人性恶假设是人治和专制治理的理论基础;理性主义人性恶假设是法治的理论基础.人性善强调了道德自律的可能性,但缺乏预警机制,理性主义人性恶的不足在于过分强调人性中的阴暗,忽略了人的主动性.理想的治理结构应该是德治与法治的统一,其理论基础是理性与非理性,善与恶相统一的人性论假设.理想的治理结构应该是德治与法治的统一,其理论基础是理性与非理性,善与恶相统一的人性论假设. 相似文献
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44.
台北国际无车日自2002年起举办了5次,由最早的骑自行车活动扩大至包含“走路上学日”与“公共交通月”丰富多彩的系列活动,渐渐获得民众认同。无车日活动的目标是通过活动的倡导和社会参与来改变民众使用交通工具的行为,潜移默化的效应可促使形成可持续交通政策,当可持续交通政策与基础设施建设落实后又可具体改变交通环境,形成良性的循环机制。首先说明了“无车日”的由来,并回顾台北都会区过去5年来举行无车日系列活动的内容与经验,同时基于活动的发展与成果归纳出无车日活动的成功要素,最后提出未来活动将扩大举办的内容、方式与展望,以期能为其他城市作参考。 相似文献
45.
Intergraph Smart 3D软件的电缆敷设功能在化工电力行业应用较为广泛,考虑到邮轮电气生产设计中的电缆具有长度长(3 000 km~5 000 km)、种类多、通道网络复杂和分段敷设的特点,直接应用Smart 3D原生的电缆敷设功能进行电缆敷设存在较大的风险。从邮轮电缆敷设需求出发,对Smart 3D原生电缆敷设解决方案进行优化,充分考虑电气设计人员的使用习惯,基于贪心算法和单源最短路径算法(Dijkstra算法)优化算法解决断续托架的电缆敷设和电缆分区敷设最优路径选取的问题,提高电气设计人员的电缆敷设效率。 相似文献
46.
Currently, the shipping industry is facing a great challenge of reducing emissions. Reducing ship speeds will reduce the emissions in the immediate future with no additional infrastructure. However, a detailed investigation is required to verify the claim that a 10% speed reduction would lead to 19% fuel savings (Faber et al., 2012).This paper investigates fuel savings due to speed reduction using detailed modeling of ship performance. Three container ships, two bulk carriers, and one tanker, representative of the shipping fleet, have been designed. Voyages have been simulated by modeling calm water resistance, wave resistance, propulsion efficiency, and engine limits. Six ships have been simulated in various weather conditions at different speeds. Potential fuel savings have been estimated for a range of speed reductions in realistic weather.It is concluded that the common assumption of cubic speed-power relation can cause a significant error in the estimation of bunker consumption. Simulations in different seasons have revealed that fuel savings due to speed reduction are highly weather dependent. Therefore, a simple way to include the effect of weather in shipping transport models has been proposed.Speed reduction can lead to an increase in the number of ships to fulfill the transport demand. Therefore, the emission reduction potential of speed reduction strategy, after accounting for the additional ships, has been studied. Surprisingly, when the speed is reduced by 30%, fuel savings vary from 2% to 45% depending on ship type, size and weather conditions. Fuel savings further reduce when the auxiliary engines are considered. 相似文献
47.
The corporate average fuel economy (CAFE) standard is the major policy tool to improve the fleet average miles per gallon of automobile manufacturers in the US. The Alternative Motor Fuels Act (AMFA) provides special treatment in calculating the fuel economy of alternative-fuel vehicles to give manufacturers CAFE incentives to produce more alternative-fuel vehicles. AMFA has as its goals an increase in the production of alternative-fuel vehicles and a decrease in gasoline consumption and greenhouse gas emissions. This paper examines theoretically the effects of the program set up under AMFA. It finds that, under some conditions, this program may actually increase the production of fuel-inefficient gasoline vehicles, gasoline consumption and greenhouse gas emissions. 相似文献
48.
Ching-Chih Chang Chih-Min Wang 《Transportation Research Part D: Transport and Environment》2012,17(3):185-189
The paper evaluates the effectiveness of strategies designed to reduce these pollutants in port areas, based on a newly developed assessment model to calculate emissions. The case study found that the strategy of reducing the ship’s speed to 12 knots is most effective in cutting fuel consumption and costs, as well as emissions. Adopting an onshore power supply system could reduce CO2 emission by 57.16% and PM by 39.4%. By adopting the strategies of both reduced speed and cold ironing emissions control, a reduction in emissions of 71% to 91% can be achieved with a 20 nautical mile reduced speed zone. Therefore, the goals of reductions in emissions to improve port areas air quality could be achieved through adopting a green port policy in the future. 相似文献
49.
Chen Chen 《Maritime Policy and Management》2018,45(7):944-961
Ports and cities are intrinsically linked. Port city, which serves as a link between the local and global economy, is an integration of both urban and port systems. Constrained by different regional structures, port cities have developed various formulations over time. Using a two-stage data envelopment analysis (DEA) approach, this paper proposes a new method for measuring the sustainable development of different port city systems. While the previous empirical studies often separate the port system and the urban system, this paper assesses the two systems in an integrated way. Moreover, this paper develops a systematic methodology for measurement of sustainability. Twenty world-leading container port cities are selected for this study using contemporary data. The DEA results display their relative differences in levels of sustainable development, which reveal the effectiveness of the prevailing policies in them. Eventually, recommendations are drawn for other port cities by referring to the best practices. 相似文献
50.
This paper extends the work on Pareto-improving hybrid rationing and pricing policy for general road networks by considering heterogeneous users with different values of time. Mathematical programming models are proposed to find a multiclass Pareto-improving pure road space rationing scheme (MPI-PR) and multiclass hybrid rationing and pricing schemes (MHPI and MHPI-S). A numerical example with a multimodal network is provided for comparing both the efficiency and equity of the three proposed policies. We discover that MHPI-S can achieve the largest reduction in total system delay, MHPI can induce the least spatial inequity and MHPI-S is a progressive policy which is appealing to policy makers. Furthermore, numerical results reveal that different classes of users react differently to the same hybrid policies and multiclass Pareto-improving hybrid schemes yield less delay reduction when compared to their single-class counterparts. 相似文献